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A fun, free platform for learning modern cryptography

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Learn By Doing

Learn about modern cryptography by solving a series of interactive puzzles and challenges. Get to know the ciphers and protocols that secure the digital world by breaking them.

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Level Up

Earn points by solving challenges. Finish categories to earn trophies and gain levels to track your progress. Can you reach the top of the scoreboard?

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Fresh Challenges

We are constantly creating new challenges to keep your crypto knowledge up to date. Expect exciting brainteasers and whole new categories as the site continues to grow.

New Challenges
Blind (ECSC 2023 (Norway)) CTF Archive 0
WOTS Up (ECSC 2023 (Norway)) CTF Archive 0
Irish flan (ECSC 2023 (Norway)) CTF Archive 0
WOTS Up 2 (ECSC 2023 (Norway)) CTF Archive 0
Twist and shout (ECSC 2023 (Norway)) CTF Archive 0
Weekly Top Users
#1 sceleri 5005
#2 beginnerofsaigon 2645
#3 mathysEthical 1760
#4 MadRat_0 1470
#5 F0DH1L 1460
Recent Solves
Finding Flags cryptone
Lemur XOR beginnerofsaigon
RSA Starter 2 0xOsamaEid
Symmetry beginnerofsaigon
Recent Solutions
Successive Powers nk0 0
Lazy CBC nk0 0
Flipping Cookie nk0 0
Greatest Common Divisor Psi505 0
Extended GCD yasser_rafid 0

Level Up

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